Syria is Iran's only ally in the Arab world. It's their route to the sea.

As you can see above, Iran actually has extensive coastline—the Caspian Sea, the Persian Gulf (named after, you know, the Iranian precursor Persia) and the Gulf of Oman. Meanwhile, Syria doesn't even share a border with Iran.

So pretty clear cut, right? Romney is a moron, and basic geography rebuts his idiocy. Ah, but never underestimate the ability of conservatives to defend their own against reality. In this case, the honors go to National Review neocon Greg Pollowitz, who argues that Romney was right!